1. Field of the Invention
The present invention relates to a waste toner collecting apparatus for collecting waste toner used in an electronic photography type copying machine, a printer or the like adapted to produce a color image by laying toner images of a plurality of different colors one on the other. This invention also relates to an image forming apparatus and a process cartridge to be used in an image forming apparatus.
2. Description of the Related Art
A cleaning apparatus such as a blade is normally operated to remove toner remaining on a photosensitive member of an image forming apparatus such as a copying machine or a printer after the end of an image transfer process. The toner removed from the photosensitive member is collected in a waste toner box as waste toner. When the waste toner box becomes full, it is replaced by a new one.
Tandem type image forming apparatus have been marketed in recent years. A plurality of image forming units, each having a photosensitive member, are arranged in parallel in a tandem type image forming apparatus and the toner images of different colors formed on the respective photosensitive members are transferred onto a single sheet and laid one on the other to produce a color image. Apparatus have been developed for such a tandem type image forming apparatus to collect the residual toner produced from a plurality of photosensitive members and an intermediate transfer belt in a single waste toner box. When the waste toner box becomes full, it is replaced by a new one.
Among such apparatus, some are equipped with a device for preventing waste toner from spilling if a waste toner conveying section and the waste toner box are moved away from each other during the operation of replacing the waste toner box. For example, Jpn. U. M. Registration No. 2517201 discloses the use of shutters for preventing waste toner from spilling.
The known device interlocks the operation of opening/closing the shutters and that of mounting/dismounting a waste toner container. More specifically, two shutters are opened and closed with a time lag to prevent waster toner from spilling when the shutters are operated during the process of mounting or dismounting the waste toner container. Thus, the device is structurally complex and requires high manufacturing cost. Particularly, a number of shutters have to be installed at high cost when such a device is used for a tandem type image forming apparatus having a plurality of image forming units aligned.
Therefore, there is a demand for a waste toner collecting apparatus, an image forming apparatus and a process cartridge of image forming apparatus, to be used for an image forming apparatus including a replaceable waste toner box, which is structurally simple, can reliably prevent waste toner from spilling when replacing the waste toner box and also can prevent the operation errors when replacing the waste toner box. As a result, it is obtaining the safety and the reduction of cost.